LED Technolgy What do you think?

[movingheadfan]

There are now many new LED lighting fixtures on the market and we know they are getting brighter all the time.

 

But, can they really completely replace halogen and discharge lamps, maybe in the smaller fixtures but think about the huge outdoor events where brightness matters.

 

Are LED really bright enough to take over?

[paulears]

Well, after seeing the shootout at PLASA, I'd say a yes - there now are LED fixtures that can sit side by side with our more common fixtures - BUT I couldn't possibly justify the price - which appears to be four to five times the price of a conventionally lamped source. I also noted that many of the brighter units also have pretty high current demands - quite a few had figures over a KW.

 

So it's now possible to go to your favourite manufacturer, Robert Juliat, and the others, and buy an LED version that looks and feels the same. They just cost more!

[ramdram]

There's a certain irony here...the earlier leds were clearly not as bright as was useful...other than washes say...no equivalent, then so to speak, to Par 64s in the LED "range". Now it is possible to get decently bright leds, comparable to said Par 64. Yet they are hugely more expensive and are not quite the energy savers we all hoped for.

 

It would be difficult for a lot of places to justify the cost of changing all your lanterns to leds on the energy ticket owing to the initial cost (no doubt the threatened double dip will predicate very decent discounts just to shift stock) because of the cost of electricity. Unless of course you happen to be very well backed and supported with bequests and the like.

 

However, if a Par 64 goes down then a new bubble is going to be around £25 say...and is simplicity itself to replace. We read of some individual leds going in the lantern unit and sorting out a replacement led (as a component) is not quite so easy and a certain amount of skill and or cash is required.

 

Plus, if as remarked earlier in the thread, these new led lanterns are quite greedy for power then the notion of simply hanging a few off a 13A circuit becomes less practicable.

[timmeh2]

Hi

 

I think we're a long way off from a LED 64 being as bright as, or having the same even colour output as a good old CP62 with a gel in front of it.

 

Also personally I wouldn't be in any rush to replace any of my generics with the stuff as it would render all my dinner channels useless.

 

All the best

Timmeh

[lite_lad]

what about something like this?

 

http://www.evolight.it/pagina_prodotti/linea-lampade-led/evoled.htm

 

which I have seen myself in an acclaim fresnel and it is of comparable output to a standard 650w acclaim fresnel lamp, and looked of a similar colour temperature (although I would have had to see them side by side to make a decent comparison)

 

It is also dimmable and simply fits into existing fixture, but bring the advantages of less heat (which is great if your in a studio space, which is likely with these fixtures!) and this particular model saves significantly on energy (0.3A compared to 2.8A for the tungsten 650w)

 

maybe this is the kind of thing we should be looking at?

[bigclive]

LED is finding its own market in specific applications where lower intensity and saturated colours are involved. It's this whole thing about replacing every other light source with LED because it's the latest technology. Many of the lights at PLASA were very impressive and I'd say that the saucepan-in-a-yoke LED wash lights were defining a new standard of their own.

 

However, LED is still not as efficient as a metal halide source for many applications, so it will not replace them in the immediate future.

 

We've still to see how many of these fixtures pushing the LEDs hard will deal with even the slightest build up of fluff in their extensive cooling systems. Halogen and halide sources handle high temperatures fine. LED does not and will rapidly fail above a temperature point.

[GreatBigHippy]

This is exactly the thing I am wrestling with at the moment. We have a refresh of facilities coming up in our 2nd large space and a studio space. The large space also needs new dimmers for a variety of reasons.

Although I agree that the cost savings on electricity do not make the economic argument very strong I think there are a few other good reasons, some of which have been alluded to.

- Reduced HVAC requirements. Studio theatres in particular suffer from this, at least the ones I frequent. A comfortable audience is a happy audience. And there is also a minuscule saving but definite benefit in not pumping all your haze outside as fast as you can produce it :)

- Reduced weight. Many of the LED movers I saw at PLASA were an awful lot lighter than their traditional cousins. That makes them safer for moving and rigging. And means you can fit some more on your bars.

- Brightness. This year was the first year that I saw fixtures that equaled decent profiles for brightness in whites. That being said, LEDs have had an edge on standard pars for a little while when reproducing deep colour. The fact that this is additive rather than subtractive means there is greater efficiency there also. There has also got to be an argument for time/money saving for cutting and fitting gels. Which brings me to..

- Colour. Now, I know that there is no such things as a "standard" rig. You will always need to be swapping stuff around. But If you have a 3 colour wash you only need 2/3 of the lanterns (two are needed to facilitate smooth fades). And I would say for some studios, and for venues that do a lot of rock and roll, comedy etc. it surely means less faffing about it going up to change wash gels every time. Thus being inherently safer.

- If your dimmers are up for refresh then it may start to make more sense to replace the lot with hard power. Still doing my sums on this to see if it saves much money. Got to save some money on copper for a new install though ;)

- Ecologically, less power draw over all has got to be a good thing. Even if the electricity savings don't make a great economic argument. As was said, if you have altruistic giving helping with the purchase then it is a good argument for going LED.

- Lamp life. The near guarantee that you'll never lose a lamp in a show, or during a focus has got to be a good thing. Although conversely, as has been said, if they do go wrong, they need much more skill and expertise to repair.

 

I would invite now for all of this to be shot down in flames. As I say, I am currently wrestling with the pros and cons of the switch.

If nothing else, it is a very exciting time for change. It'll be exciting to see what comes in over the next 5 years or so :)

[Tomo]

what about something like this?

 

http://www.evolight.it/pagina_prodotti/linea-lampade-led/evoled.htm

Did you see the full dimming curve?

What's it like at low levels?

How much of the Fresnel zoom is still usable and looks 'right'?

 

I know quite a few venues who might be interested in those, however I don't believe the datasheets and sales docs as they are contradictory (could be a translation error), and I've never met anyone who has actually seen the full dimming curve.

 

The videos they put on YouTube always snapped straight to full, and they really looked like you had to completely dismantle the fixture to fit them and they're so huge that it looked like there was no zoom range left in the fresnel.

[musht]

>>huge outdoor events where brightness matters.

 

>>Are LED really bright enough to take over?

 

As profiles ,no.

 

Washlights in colours, yes.

 

>>Robert Juliat, and the others, and buy an LED version that looks and feels the same

 

Someone has to say it, much as have respect for RJ , the Lancelot is an outstanding lite, the Aledin is a patched together heap of dung brought to market to answer perceived market demand not because the technology was ready. Try finding the photometrics for it....

 

>>these new led lanterns are quite greedy for power

 

Really important point, lighting IS an energy intensive activity, Source One, the Sun, is certainly not a low energy device, if you need it bright it is going to use substantial amounts of energy.

 

Imagine someone trying to sell you low energy heating.

 

>>what about something like this?

 

>>http://www.evolight....-led/evoled.htm

 

Someone left their light meter in their other jacket, like RJ, no photometrics...

 

Its easy to make something look good in isolation in a darkened room or against selected competition, Clive has a story about original High End Emulator looking good in a darkened demo room.

 

Fresnel is probably a better option for LED retrofit than a profile but still hit boundaries of power density, in general halogen has more light per mm^2, which lens has to gather and get out the front.

 

>>LEDs hard will deal with even the slightest build up of fluff in their extensive cooling systems

 

Regarding some of these units as maintenance free might be a mistake, RDM feedback of temp with alarms at the desk and a case of canned air on hand at all times, is probably good insurance.

 

- Reduced HVAC requirements. Studio theatres

 

Pretty much no argument there, but studio theatres is probably more the range of current LED profiles.

 

- Reduced weight

 

Not always true, lot of heatsink and PSU on larger LED units.

 

- Brightness. This year was the first year that I saw fixtures that equaled decent profiles for brightness in whites

 

Must have missed the LED S4 575 equivalent at PLASA, but then wasn`t in a darkened demo room, see above.

 

- Colour

 

The Evo LED thing and Aledin are white LED sources , still needing gel , but filtering a different spectrum from tungsten, colour temp is an appearance not a spectrum ;-)

Prism Reveal was an additive 6 colour , equivalent output to about 400W halogen in white.

For anything that isn`t required to project a pattern, its getting harder to justify the dimmers cable and lamps, cost has fallen and brightness risen that especially for smaller spaces, LED is more than cost competitive.

 

- If your dimmers are up for refresh then it may start to make more sense to replace the lot with hard power

 

Always be a use for some dimming, but mebbe hard power and distributed dimming, bearing in mind noise, bzzzz, from the rig in a studio.

 

- Ecologically, less power draw over all has got to be a good thing.

 

er,um, we`ll just leave out the messy side of semiconductor manufacture, of course LEDs are Green, repeat mantra, rinse, repeat ;-)

 

- Lamp life.

 

Useable lamp life is still an unknown, oft quoted 50Khrs to 70% is projected for one LED living a chilled life in ideal conditions. More realistic is think of working life of 20Khrs before its either too dim or more economic to replace with new generation, by which point its value is probably negative, no s/h value but chargeable WEEE waste.

 

Sure Ynot will be in with some intersting obsevations as he switched to a large amount of LED recently.

[bigclive]

One other LED advantage. They don't go boom and take out your optics when they fail. (At least I hope not!) On the other hand, there will ultimately be LED fixtures up in house rigs that are still in use despite their intensity falling to near useless levels. The really un-green bit is that when LEDs start going dim they usually pass as much current as when they were bright.

[kerry davies]

Throwing a spaniard in the works here, why compare LED to any other technology?

An LED lantern is a different thing entirely to a 'normal' lantern and IMO should be used for different purposes. I don't use candles in the same way as gas lights in the same way as incandescents, so why think of LED as an equivalent?

 

My current feelings are that every lighting source has its' own qualities and properties, so why not use each according to the requisite result? Discussing equivalence is not helpful, discussing best usage might be. It is what the punter 'sees' that counts, not how the illumination was generated.

 

Food for thought?

[musht]

Throwing a spaniard in the works here, why compare LED to any other technology?

 

 

Partly because it is being marketed by some quarters as the light source to replace all other light sources, this idea is quite some way removed from reality.

 

LED lantern is a lot different from a `normal` lantern. LED lites designed as LED lanterns from ground up look quite different, VLX, Glp Wash,Reveal profile.

 

Market demand is perceived as wanting LEDs in everything , so we are seeing the LED retrofits and LED versions of other lanterns appearing, its just like the XYZ3500 but its LED!

 

Translated, its just like XYZ3500 because it uses all the same casings, much the same optics with a changed out condenser at the source end,its about 10% of the power and similar brightness and four times the cost, but its LED! ;-)

[Don Allen]

I started out looking for LED's as a replacement for conventional lighting, but now treat them as another category, with their pro's and con's. One of the con's is DMX channels, my LED cyc lights are 17 channels each, my LED Par's are 9 channels each.

 

Weight is always going to be higher if you want to keep fan noise down or left out altogether. Most of the shows I do are in small venues, 200 - 400, so the patrons can hear something new, fan noise. I am probably more consious of it than they are. My LED Par replacements are the ETAN 48 x 5w RGBA Multipar Emperor which weighs 7.5kg. I use a Colourset scroller which weighs 2.3 kg on my PAR64 so the LED Par is twice a heavy. It has a fan. My first attempt at LED cyc replacements is a 84 x 4w LED BAR-84W-4PIXEL-RGBW unit from Mumedia has two fansand weighs 4.8kg which is lighter than my Strand Coda4 which weigh 10 kg. These units are 25 degrees which is too narrow, but match the Coda4 in subjective light level. If I want a fanless version, the weight will be about 12 kg as you have to have lots of aluminium heat sinking.

 

Power savings are working out ok, as both units draw 25% of the units they are replacing. This is for smaller stages, I would expect only a 50% saving on power for larger stages.

 

What I appreciate the most is the availability of colour. It cuts down my gel costs, rigging time, access to the stage is not required during tech rehearsals and the director can stand alongside me while we look through the swatch book in Lightfacotry 2 and try different colours.

 

They will take years to pay for themselves, I am subsidising their purchase from my businesses maintenance jobs.

[Ashley R]

 

http://www.evolight....-led/evoled.htm

 

 

Very interesting, I would quite like to see one for myself, fitted into a Acclaim, sitting next to one fitted with a T27 lamp, both running @ 240V. I wonder what they go for?

 

 

I started out looking for LED's as a replacement for conventional lighting, but now treat them as another category, with their pro's and con's. One of the con's is DMX channels, my LED cyc lights are 17 channels each, my LED Par's are 9 channels each.

 

I always look out for fixtures with 3CH DMX capabilities if im going to be using then as a wash fixture, all of my LED pars have either got a 3 or a 6ch mode, and they almost always are in 3ch mode, as I have no use for Strobe/Master Dim/ Macro's when doing stage washes. LED cycbar/ Wash bar fixtures I would be looking at 3/9/whatever CH functionality, again giving me control over how much functionality I need.

 

Weight is always going to be higher if you want to keep fan noise down or left out altogether. Most of the shows I do are in small venues, 200 - 400, so the patrons can hear something new, fan noise. I am probably more consious of it than they are. My LED Par replacements are the ETAN 48 x 5w RGBA Multipar Emperor which weighs 7.5kg. I use a Colourset scroller which weighs 2.3 kg on my PAR64 so the LED Par is twice a heavy. It has a fan. My first attempt at LED cyc replacements is a 84 x 4w LED BAR-84W-4PIXEL-RGBW unit from Mumedia has two fansand weighs 4.8kg which is lighter than my Strand Coda4 which weigh 10 kg. These units are 25 degrees which is too narrow, but match the Coda4 in subjective light level. If I want a fanless version, the weight will be about 12 kg as you have to have lots of aluminium heat sinking.

 

This is also one thing I am also very concious about, the fan noise. I have some PAR 64's which have got fans in them that spin at a very very high RPM and make one hell of a noise, good thing they are only 6deg and are only used for long throw applications, whist my main LED stock does have fans in them, but they are tiny, and become inaudible at 0.5m, but they do weigh a bit, about 4-5kg from memory.

 

also do you think you could provide a link to both those fixtures?

 

Power savings are working out ok, as both units draw 25% of the units they are replacing. This is for smaller stages, I would expect only a 50% saving on power for larger stages.

 

What I appreciate the most is the availability of colour. It cuts down my gel costs, rigging time, access to the stage is not required during tech rehearsals and the director can stand alongside me while we look through the swatch book in Lightfacotry 2 and try different colours.

 

They will take years to pay for themselves, I am subsidising their purchase from my businesses maintenance jobs.

 

the avalibility of colour mixing is wonderful! Not needing to carry a large gel stock, and spending tonnes of time up and down a ladder is great. And being able to show the director what everything will look like in real time makes them quite happy as well, as they will quite regularly ask could I have a look at this, this or this all in the space of 30 seconds, and I can quite easilly do so.

 

Also not needing multiple dimmer racks, and tonnes of Wieland (Socca) Looms running everywhere is a bonus, and most are happy they are just derigging tonnes of LED's and coiling tonnes of 10A power and data instead of 3Ph cabling and looms.

 

 

*Apolagies for any spelling mistakes, typing all of this on a Japenese keyboard has prooved challenging! (There are more buttons than an english one, and where things are is slightly different)

[ramdram]

Absolutely fascinating, "new" aspects of LEDs being revealed everyday.

 

I was intrigued by the weight issue. It's all very well to have a rig capable of supporting "n" kgs but if the weight of the replacement LEDs is greater than the kit being replaced then that's an issue for the budget deficit side, ie beefier grids and bars perhaps. And, if you found that you need more because of a lesser light o/p per unit lantern?

 

Then the DMX channels required; which again may need to be examined in acute financial detail, as in new desks perhaps.

 

The alleged power savings are also an issue. Paulears remarked that some of these very new, very powerful units were not exactly sipping energy. It may be that even for LEDs that to get sufficient light o/p the energy required becomes greater in a non-linear way?

 

Ref the "surplus" dimmers which may flood the used kit market; if the smaller theatres wanted to upgrade ancient dimmers then it may be them who benefit most by acquiring decent kit quite cheaply to drive their Pars and Cantatas etc. Those theatres may not have that many perfs cf the West End, say, and a switch to LEDs would be a pointless exercise anyway.

 

Then the repair of some LED components is not going to be cheap. The question of a gradual fall off in light output or a possible tendency to change colour over the years has to be considered, again in the financial budget dept. Has anyone any predictions of how much to service and repair LED movers, say, should they become common currency perhaps? No, how could they?

 

It is almost as if we are seeing a parallel evolution thing and this LED "branch" becomes a dead end? (I see similar in the ISM band radio mics too. Nobody knows the full extent of how these devices may affect regular wifi or wireless DMX.)

 

Granted some posters make positive points in the areas of instant colour changes and for washes there may indeed be a saving in energy. However at Plasa we saw that the aim of a few manufacturers was to compete directly with Pars or profile types, say, but at stupendous cost. Obviously the R&D has to be costed and factored into the retail price. But if you are constantly innovating then this R&D cost may be ever present in the price.

 

At present it does seem that it is going to cost a lot simply to save a little on energy costs.